March 1, 2016

How much water do you need?

LET’S JUST SAY the two of you are in
mid-Pacific when your boat hits a whale. You have to abandon ship and climb
into a life raft. Your first reaction is shock, and that’s likely to last a
week or so until you can get your lives properly organized. By that, I mean organize
shelter from the elements, work out a plan for navigation, keep a proper watch
for passing ships, and find enough food and water to keep you alive.

One of your immediate priorities
will be to ration the water supply. You’ve found four or five cans of fresh
water inside the liferaft — about two gallons, if you’re lucky. How much should
you dole out while you’re still in a state of shock, before you can think
coherently about how to catch rainwater, or catch fish to squeeze the potable
liquids out of them?

Does three small cups each per day
sound about right? Can you actually live on only three cups a day? Each cup is
about six ounces, so two gallons should last six days. We all know that most
humans can last three days or so without water, and about a month without food,
but at the end of six days you won’t have any water left.

So should you reduce your
consumption to two cups a day each?Will
that allow you to maintain the strength you need, mental and physical, to do
the organizing that needs to be done?

This is a problem that needs to be
solved immediately because if you start out by drinking your normal daily ration
of water you might run out too soon. Once it’s gone, it’s gone.In the first few days and hours it would be
all too easy to drink too much of that precious supply, so you should have
given this problem some thought previously.

It’s not a problem often discussed
in the media because every situation is different. Some lucky castaways might
have solar stills with which to make fresh water, others might have packed
hand-operated water makers in their panic bags. Some life rafts don’t have any
water at all, which is something you don’t want to discover only when your boat
sinks behind you.

So my advice is to read as many
books as you can about survival at sea, and read them now, before you go. One
of them is Steve Callahan’s Adrift: 76
Days Lost at Sea. His little single-handed sloop sank after hitting a whale
in the Atlantic and he had to take to his six-man Avon inflatable, eventually
ending up in Guadeloupe, West Indies.

Apart from the book, there’s a fine
interview with Callahan on the Cracked website by Evan V. Symon. If you’re
planning to go to sea you’ll find it very instructive: